1 Context

Considering the review from Science Advances received in February 20222, I explored the Global Climate Models from IPCC CMIP6, despite coarser spatial resolution that could not match the coastal behaviour of Arctic whales.

Three GCM at a 25 km resolution were found (“AWI-CM-1-1-MR”,“HadGEM3-GC31-MM”,“CNRM-CM6”), including Sea Surface Temperature (tos), Sea Surface Salinity (sos), Sea Surface Height (zos) and Mixed Layer Depth (mlotst). These 4 dynamic variables were first (i) extracted from CMIP6 for the historical period (1993-2014) and contemporary period (2015-2020) from ssp126. Then, each variable was included in the initial models run on the available dataset (current predictions: “present”).

The results here are presented for summer only.

2 Model performance

Three new dynamic variables were added to each model (SSS, MLD and SSH), which improved the performance of the algorithms on the tracking data (“present distribution”).

2.1 Bowheads

\label{fig:figs}Boxplot of the performance metrics for bowheads in summer (AWI-CM-1-1-MR).

Figure 2.1: Boxplot of the performance metrics for bowheads in summer (AWI-CM-1-1-MR).

2.2 Narwhals

\label{fig:figs}Boxplot of the performance metrics for narwhals in summer (AWI-CM-1-1-MR).

Figure 2.2: Boxplot of the performance metrics for narwhals in summer (AWI-CM-1-1-MR).

2.3 Belugas

\label{fig:figs}Boxplot of the performance metrics for belugas in summer (model: AWI-CM-1-1-MR).

Figure 2.3: Boxplot of the performance metrics for belugas in summer (model: AWI-CM-1-1-MR).

The Random Forest suffers from overfitting, so the best algorithm for each species is: GBM for belugas, narwhals East and bowheads West, BRT for narwhals West and MARS for bowheads East.

3 Variable importance

\label{fig:figs}Boxplot of the performance metrics for belugas in summer.

Figure 3.1: Boxplot of the performance metrics for belugas in summer.

Most important variables are:

  • distance to coast for belugas and narwhals West;

  • SSH for narwhals East;

  • SSS for bowheads West;

  • SST for bowheads East.

4 Predictions Belugas

4.1 BRT

\label{fig:figs}mean prediction maps for Belugas in summer (present) from the BRT.

Figure 4.1: mean prediction maps for Belugas in summer (present) from the BRT.

4.2 MARS

\label{fig:figs}Mean prediction maps for belugas in summer from the MARS.

Figure 4.2: Mean prediction maps for belugas in summer from the MARS.

4.3 GBM

\label{fig:figs}Mean prediction maps for belugas in summer from the GBM.

Figure 4.3: Mean prediction maps for belugas in summer from the GBM.

4.4 Max GBM

\label{fig:figs}Max prediction maps for belugas in summer from the GBM.

Figure 4.4: Max prediction maps for belugas in summer from the GBM.

4.5 GAM

\label{fig:figs}Mean prediction maps for belugas in summer from the GAM.

Figure 4.5: Mean prediction maps for belugas in summer from the GAM.

4.6 GLM

\label{fig:figs}Mean prediction maps for belugas in summer from the GLM.

Figure 4.6: Mean prediction maps for belugas in summer from the GLM.

4.7 RF

\label{fig:figs}Mean prediction maps for belugas in summer from the RF.

Figure 4.7: Mean prediction maps for belugas in summer from the RF.

4.8 Max RF

\label{fig:figs}Max prediction maps for belugas in summer from the RF.

Figure 4.8: Max prediction maps for belugas in summer from the RF.

5 Predictions Narwhals

5.1 BRT

\label{fig:figs}Mean prediction maps for Narwhals in summer (present) from the BRT.

Figure 5.1: Mean prediction maps for Narwhals in summer (present) from the BRT.

5.2 MARS

\label{fig:figs}Mean prediction maps for Narwhals in summer from the MARS.

Figure 5.2: Mean prediction maps for Narwhals in summer from the MARS.

5.3 GBM

\label{fig:figs}Mean prediction maps for Narwhals in summer from the GBM.

Figure 5.3: Mean prediction maps for Narwhals in summer from the GBM.

5.4 GAM

\label{fig:figs}Mean prediction maps for Narwhals in summer from the GAM.

Figure 5.4: Mean prediction maps for Narwhals in summer from the GAM.

5.5 GLM

\label{fig:figs}Mean prediction maps for Narwhals in summer from the GLM.

Figure 5.5: Mean prediction maps for Narwhals in summer from the GLM.

5.6 RF

\label{fig:figs}Mean prediction maps for Narwhals in summer from the RF.

Figure 5.6: Mean prediction maps for Narwhals in summer from the RF.

5.7 Max GBM

\label{fig:figs}Max prediction maps for Narwhals in summer from the BRt West and GBM East.

Figure 5.7: Max prediction maps for Narwhals in summer from the BRt West and GBM East.

6 Predictions Bowheads

6.1 BRT

\label{fig:figs}Mean prediction maps for Bowheads in summer (present) from the BRT.

Figure 6.1: Mean prediction maps for Bowheads in summer (present) from the BRT.

6.2 MARS

\label{fig:figs}Mean prediction maps for Bowheads in summer from the MARS.

Figure 6.2: Mean prediction maps for Bowheads in summer from the MARS.

6.3 Max MARS

\label{fig:figs}Max prediction maps for Bowheads in summer from the MARS.

Figure 6.3: Max prediction maps for Bowheads in summer from the MARS.

6.4 GBM

\label{fig:figs}Mean prediction maps for Bowheads in summer from the GBM.

Figure 6.4: Mean prediction maps for Bowheads in summer from the GBM.

6.5 Max GBM

\label{fig:figs}Max prediction maps for Bowheads in summer (present) from the GBM.

Figure 6.5: Max prediction maps for Bowheads in summer (present) from the GBM.

6.6 GAM

\label{fig:figs}Mean prediction maps for Bowheads in summer from the GAM.

Figure 6.6: Mean prediction maps for Bowheads in summer from the GAM.

6.7 GLM

\label{fig:figs}Mean prediction maps for Bowheads in summer from the GLM.

Figure 6.7: Mean prediction maps for Bowheads in summer from the GLM.

6.8 RF

\label{fig:figs}Mean prediction maps for Bowheads in summer from the RF.

Figure 6.8: Mean prediction maps for Bowheads in summer from the RF.